Updates always download full app, not patch

[abenzick]

Hello,

I'm having great success with Tufup but I've noticed that whenever I push updates, the app always downloads the full version of the application. My app is around 80mb and I do really small patches. Tufup generates the patches in new targets and they are around 700kb size. Existing users get notified there's an update but instead of downloading the 700kb patch, it downloads the 80mb file each time.

I'm using tufup 0.9.0 and I feel like the metadata and the targets are getting generated properly. Here is an example of the targets meta data below. Any suggestions of what I'm doing wrong?

  "AMP-1.2.9.patch": {
    "custom": {
      "tufup": {
        "tar_hash": "XX",
        "tar_hash_algorithm": "sha256",
        "tar_size": 85882880
      },
      "user": null
    },
    "hashes": {
      "sha256": "XX"
    },
    "length": 1143453
  },
  "AMP-1.2.9.tar.gz": {
    "custom": {
      "tufup": {
        "required": false
      },
      "user": null
    },
    "hashes": {
      "sha256": "XX"
    },
    "length": 85003534
  },

[dennisvang]

[...] Existing users get notified there's an update but instead of downloading the 700kb patch, it downloads the 80mb file each time.

Hi @abenzick, thanks for the detailed report.

I'm not sure what causes this, but here's the logic used to decide whether to do a patch update:

tufup/src/tufup/client.py

Lines 246 to 247 in 473045f

	if not patch or no_patches or patch_too_big or no_archive or abort_patch:
	# fall back on full update

To summarize:

• patch: value of the patch arg specified in check_for_updates() (default True)
• no_patches: no patches found
• patch_too_big: patch found, but almost as big as the archive itself
• no_archive: no archive found, so cannot apply patch
• abort_patch: true if any of the new patches have failed on a previous run

Does any of those look like a likely culprit to you?

If you could run your app with log level DEBUG, that could help us figure this out.

(note to self: more fine-grained debug logging would have been convenient here...)